1. Field of the Invention
The present invention relates to a pin jack to be mounted on an electric appliance such as a video camera or the like.
The pin jack of the type above-mentioned generally comprises (i) a casing body forming an electrical plug insertion space (hereinafter referred to as the plug insertion space) into which an electrical plug serving as the counter member for this pin jack (hereinafter referred to as plug) is to be inserted, and (ii) a movable contact piece adapted to resiliently come in contact with the plug. When the plug is inserted into the plug insertion space in the casing body, the contact formed on the plug resiliently comes in contact with the contact of the movable contact piece.
2. Description of the Prior Art
The pin jack of the prior art of the type above-mentioned is described in Japanese Utility Model Laid-Open Publication No 61-4378. As shown in FIG. 4, this conventional pin jack comprises a movable contact piece 100, a stationary piece 110 integral with the movable contact piece 100, a casing body 210 forming, in its inside, a plug insertion space, a stationary piece housing portion 220 integrally formed at the rear end of the casing body 210. The stationary piece 110 integrally extends from the base end of the movable contact piece 100 rearwardly thereof and is provided at a suitable portion thereof with an engagement pawl 111.
In the pin jack in FIG. 4, the movable contact piece 100 is assembled in the inside of the casing body 210 such that the longitudinal direction shown by an arrow A) of the movable contact piece 100 extends along the longitudinal direction (axial direction shown by an arrow B) of the casing body 210. In this assembled state, the stationary piece 110 is inserted into grooves 221 of the contact piece housing portion 220 and the engagement pawl 111 is engaged with a suitable portion of the inner surface of the stationary piece housing portion 220.
According to this pin jack, the movable contact piece 100 is positioned inside of the casing body 210 by both the stationary piece inserted into the stationary piece housing portion 220 and the engagement pawl engaged with the inner surface of the stationary piece housing portion 220.
In the pin jack above-mentioned, the movable contact piece 100 is assembled in the inside of the casing body 210 such that the longitudinal direction (shown by the arrow A) of the movable contact piece 100 extends along the longitudinal direction (shown by the arrow B) of the casing body 210. In this pin jack, when the stationary piece 110 rearwardly extends from the base end of the movable contact piece 100, it is inevitably required that the stationary piece housing portion 220 for fixing the stationary piece 110 to position the movable contact piece 100 is integrally formed at the rear end of the casing body 210. In addition, the movable contact piece 100 is required to be long enough to provide suitable resiliency is given thereto. As to the stationary piece 110, it is required that, when fixed to the stationary piece housing portion 220, the stationary piece 110 should be firmly fastened and the stationary piece 110 should have such length (projecting length from the base end of the movable contact piece 100) as to assure a predetermined attaching strength.
However, if the lengths of the movable contact piece 100 and the stationary piece 110 are so determined as to satisfy the requirements above-mentioned, the entire length of the structure including both the movable contact piece 100 and the stationary piece 110 is lengthened. This inevitably lengthens the required length of the jack body 200 including the stationary piece housing portion 220 and the casing body 210 which houses the movable contact piece 100 and the stationary piece 110.
In a recent AV appliance such as a video camera, a stereo set or the like, it is required to reduce the entire configuration in size and to increase the mounting density of a variety of electric or electronic components. In this connection, the pin jack above-mentioned is also strongly required to be made in a compact design.